Throughout the industrial art, elongate coil tension springs are widely used. Such springs are most commonly provided with mounting loops, rings or apertured plates at their terminal ends to facilitate connecting them in and with related mechanisms. It is not infrequent that such springs, when installed in or removed from their related mechanisms, must be manually tensioned and elongated in order to connect or couple them in and with their related mechanism. In many instances, such springs are so large and strong that they are extremely difficult to manually tension for installation and are do disposed to the mechanisms with which they are related that to manually tension, elongate and install them is extremely awkward and difficult.
The difficulties and problems associated with elongating and installing elongate coil tension springs are commonly associated with and characterize the installation of such springs in those counter-balanced hinge systems or hardware provided to mount garage doors and which are characterized by pivotally related links and levers fixed to and arranged between a related garage door frame and garage door and in which one or more elongate coil tension springs are engaged with and between one lever and a reactive part of the door structure, such as the garage door frame. One typical form of garage door hardware in which coil springs are employed is fully disclosed in U.S. Pat. No 3,555,590, issued Jan. 19, 1971 and assigned to Homes Hardware and Sales Co. That patented hardware is manufactured and sold by Homes-Halley Industries of Los Angeles, Calif. and is called a "jam type one-piece garage door hardware" or "pivot type garage door hardware".
Throughout the development of the art of spring loaded pivot type garage door hardware, it has been recognized that the necessity to tension and stretch the spring in such hardware to install and/or remove those springs presents a major and serious problem. In efforts to overcome that problem, the manufacturers of such hardware have sought to incorporate various spring tensioning and/or adjusting means which can be operated to make installation and removal of the springs less difficult. Most of those spring tensioning and/or adjusting means provided by the prior art have proved to be less than satisfactory for one or more reasons. Those reasons are generally peculiar to each different form of hardware and/or the environment in which it is used. Accordingly, any attempt to list and/or cite those problems which are likely to be encountered would be extremely burdensome and would serve no useful purpose.
As a result of the foregoing, the prior art has provided a number of different special means and/or devices for biasing, lengthening and otherwise working upon garage door springs to facilitate installation and/or removal of such springs in and with their related hardware. Those special means and devices disclosed in U.S. Pat. Nos. 3,014,711, 3,588,074, 3,741,558, 3,747,898 and 4,066,242 are typical of those means and devices for working on garage door springs that the prior art has offered. While certain of the above noted patented means and devices are known to have been adopted and put to use, none is known to have attained any appreciable recognition as a good and satisfactory or desirable means or device for serving its intended end. For example, that screw operated spring tensioning device or means disclosed in U.S. Pat. No. 3,741,558 has proven to be too slow and difficult to operate and further, it is such that it is often rendered inoperative by rust and the like during those protracted periods of time when its use is not resorted to.
In accordance with the above, there is an apparent yet to be satisfied need and want for an effective and efficient device for tensioning and extending garage door springs to facilitate installation and removal of such spring in and with their related garage door hardware.